According to Richard Morningstar, the Special Envoy of the United States Secretary of State for Eurasian Energy, it is important that natural gas from the Kurdish region of Iraq reaches the Southern Corridor of European energy networks.

He said Washington considered Iraq's participation in the Nabucco pipeline integral to the project.

Europe aims to break the Russian grip on the European energy sector through the so-called Southern Corridor of transit networks that includes the Nabucco pipeline.

The Nabucco consortium in Vienna said it confirmed and ordered the engineering work for feeder lines from Georgia and Iraq to connect to the main artery in Turkey.

Energy deals in Iraq require mutual agreements between the central government in Baghdad and the regional Kurdish government in Erbil. Morningstar said he hoped both sides would agree to the Nabucco terms to move the project forward.

Meanwhile, Ashti Hawrami, the Natural Resources Minister of the Kurdistan Regional Government, said at the energy conference in Istanbul that Iraq's oil and gas fields contain 100 trillion to 200 trillion cubic feet of natural gas.

"This is more than adequate for internal use, the domestic supply of Turkey as well as to satisfy the requirements of Nabucco," Hawrami was quoted as saying by Turkish English-language newspaper Today's Zaman. "We are confident, if we can prove the full 200 trillion cubic feet, we can supply the entire needs of Nabucco."